William Todd was born in Montgomery County, Pennsylvania in 1739, to Irish Immigrants Robert Todd and his second wife Elizabeth. In the French and Indian War, Todd served with the Pennsylvania troops, fought at the Battle of Kittanning, and helped capture Fort Duquesne. During the Revolution he traveled throughout the colonies and was active in Boston, joining the militia and then the Continentals, serving in major battles, including Bunker Hill, before returning to Pennsylvania. Todd served in the Pennsylvania State Constitutional Convention and the US Constitution ratifying convention. His wife was Hanna Davis, who he married 1776. He died in Unity, Westmoreland County on October 10, 1810. His grand niece Mary Todd would later become Abraham Lincoln's wife.